Re: [syzbot] [arm?] WARNING in do_sve_acc

[Will Deacon]

[+Broonie and Mark R as I'm sure we've seen this one before, possibly
 in a report from Naresh? Was it a QEMU issue?]

On Tue, Dec 19, 2023 at 03:58:24PM -0800, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    3f7168591ebf Merge tag '6.7-rc5-smb3-client-fixes' of git:..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=108baf71e80000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=8cf3c4f966189832
> dashboard link: https://syzkaller.appspot.com/bug?extid=95ffb6a83b20ea7f4f55
> compiler:       aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> userspace arch: arm64
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/384ffdcca292/non_bootable_disk-3f716859.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/fc2a62c05f31/vmlinux-3f716859.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/4dac83fca8af/Image-3f716859.gz.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+95ffb6a83b20ea7f4f55@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 16446 at arch/arm64/kernel/fpsimd.c:1394 do_sve_acc+0x6c/0x10c arch/arm64/kernel/fpsimd.c:1393
> Modules linked in:
> CPU: 0 PID: 16446 Comm: syz-executor.0 Not tainted 6.7.0-rc5-syzkaller-00134-g3f7168591ebf #0
> Hardware name: linux,dummy-virt (DT)
> pstate: 01400009 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
> pc : do_sve_acc+0x6c/0x10c arch/arm64/kernel/fpsimd.c:1394
> lr : do_sve_acc+0x5c/0x10c arch/arm64/kernel/fpsimd.c:1391
> sp : ffff800082d1be60
> x29: ffff800082d1be60 x28: fbff00000648af40 x27: 0000000000000000
> x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
> x23: 0000000080001000 x22: 0000ffffa04568d4 x21: 00000000ffffffff
> x20: fbff00000648bec8 x19: fbff00000648af40 x18: 0000000000000000
> x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
> x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
> x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
> x8 : faff000029208888 x7 : 0000000000000000 x6 : 000000000000003f
> x5 : 0000000000000040 x4 : 0000000000000000 x3 : 0000000000000001
> x2 : 0000000000000000 x1 : ffff7ffffd52e000 x0 : 0000000000800000
> Call trace:
>  do_sve_acc+0x6c/0x10c arch/arm64/kernel/fpsimd.c:1393
>  el0_sve_acc+0x2c/0x98 arch/arm64/kernel/entry-common.c:580
>  el0t_64_sync_handler+0xf4/0x12c arch/arm64/kernel/entry-common.c:708
>  el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:595
> ---[ end trace 0000000000000000 ]---
> 
> 
> ---
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